[FFmpeg-devel] about mpeg-2 audio (note - NOT AAC)

[Moritz Barsnick]

Hi Amon,
these are actually good questions for the ffmpeg-user mailing list.
(ffmpeg-devel is for discussion about the actual development of
ffmpeg.)

On Fri, Oct 23, 2020 at 19:09:18 +0000, Amon Gibson Albuquerque Nunes wrote:
> i wondered what would happen if ffmpeg had actual decoding (and
> encoding) support for MPEG-2 Audio...

It does. ffmpeg decodes MPEG-1 and MPEG-2 layer I and II.

> no it's not AAC, it's what MPEG has called a "backwards compatible"
> extension that "enhances" MPEG-1 audio that allows multichannel
> encoding of up to 5.1 channels max as well as additional sample rates
> and bitrates for MPEG-1 Audio Layer I, II, and III.

So you specifically mean MPEG-2 Part 3? With a quick search, I couldn't
find any open source encoder for that. (ffmpeg has a native MPEG layer
II encoder, as well as support for the toolame and twolame libraries.)

> i also wondered what would happen if ffmpeg had actual encoding
> support for MPEG-1 Audio Layer I.

What would happen? I guess nobody would use it. Is there any practical
use? AFAICT only Digital Compact Cassette made use of it?

Cheers,
Moritz